Parasites that have adapted to live and replicate within another cell benefit from abundant resources, protection from host immunity, and shelter from therapeutic agents. As the demands of the parasites exceed what the host cell can supply, the parasites must find a new host cell, a journey that can leave them vulnerable to nutrient deprivation and environmental stresses. Protozoa in the phylum Apicomplexa are parasites that require a eukaryotic host cell in order to replicate. Toxoplasma gondii is one such obligate intracellular parasite, capable of using virtually all warm-blooded vertebrates as host organisms (Hill et al., 2005). Acute Toxoplasma infection can cause spontaneous abortion or congenital birth defects, as well as severe disease in immunocompromised patients. This disease is widespread in the developing world and poses a significant risk to both humans and animals.
Currently, there is no effective vaccine for treating humans and only some partially effective vaccines available to treat animals. Current treatments consist of anti-folates that are problematic due to toxicity issues; therefore there is an urgent need to develop novel therapies to treat this parasitic infection. There is a dearth of effective treatments for infected humans and animals. Accordingly, there is a pressing need for compounds to vaccinate vulnerable populations and to treat infected individuals. Some aspects of the instant invention seek to address these needs.